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  • If you didn't have to play the 6 at all, would you?

    From Timothy Chow@21:1/5 to All on Sun Nov 20 13:32:51 2022
    XGID=-c-B--E-BAA-dBa----c--bbAA:0:0:1:64:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O | | O O O X |
    | X | | O O O |
    | | | O |
    | | | |
    | | X | |
    | |BAR| |
    | | | X |
    | O | | X |
    | O | | X O |
    | O X | | X X O |
    | O X X X | | X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 146 O: 163 X-O: 0-0
    Cube: 1
    X to play 64

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Timothy Chow@21:1/5 to All on Tue Nov 22 09:06:38 2022
    XGID=-c-B--E-BAA-dBa----c--bbAA:0:0:1:64:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O | | O O O X |
    | X | | O O O |
    | | | O |
    | | | |
    | | X | |
    | |BAR| |
    | | | X |
    | O | | X |
    | O | | X O |
    | O X | | X X O |
    | O X X X | | X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 146 O: 163 X-O: 0-0
    Cube: 1
    X to play 64

    I'm not sure about the answer to the question in the subject line,
    but regardless, none of the sixes is particularly pleasant to play.
    Being ahead in the race, I felt that the choice was between 24/18
    and 21/15. However, XG thinks both of those plays are whoppers
    with cheese. I think this position is a good illustration of
    Magriel's criteria, which all point toward a safe play; 9/3 may
    look ugly, but it's certainly safe.

    The variant below illustrates the same point about safety. With
    O's blot shifted to her 8pt, bar/15 becomes the safer play.

    1. Rollout¹ Bar/21 9/3 eq:+0.071
    Player: 51.19% (G:20.08% B:2.15%)
    Opponent: 48.81% (G:17.60% B:0.94%)
    Confidence: ±0.008 (+0.062..+0.079) - [100.0%]

    2. Rollout¹ Bar/21 10/4 eq:-0.009 (-0.079)
    Player: 50.27% (G:19.71% B:2.06%)
    Opponent: 49.73% (G:20.19% B:1.73%)
    Confidence: ±0.008 (-0.017..-0.001) - [0.0%]

    3. Rollout² Bar/21 24/18 eq:-0.064 (-0.134)
    Player: 49.47% (G:18.68% B:1.91%)
    Opponent: 50.53% (G:22.17% B:2.13%)
    Confidence: ±0.016 (-0.079..-0.048) - [0.0%]

    4. Rollout² Bar/15 eq:-0.096 (-0.166)
    Player: 48.77% (G:18.47% B:1.96%)
    Opponent: 51.23% (G:22.79% B:2.06%)
    Confidence: ±0.016 (-0.112..-0.080) - [0.0%]

    ¹ 5184 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller

    ² 1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller

    eXtreme Gammon Version: 2.19.211.pre-release

    -------
    Variant
    -------

    XGID=-c-B--E-BAA-dB---a-c--bbAA:0:0:1:64:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O | | O O O X |
    | X | | O O O |
    | | | O |
    | | | |
    | | X | |
    | |BAR| |
    | | | X |
    | O | | X |
    | O | | X O |
    | O X | | X X O |
    | O X X X | | X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 146 O: 160 X-O: 0-0
    Cube: 1
    X to play 64

    1. Rollout¹ Bar/15 eq:+0.009
    Player: 51.19% (G:18.54% B:1.84%)
    Opponent: 48.81% (G:20.95% B:1.80%)
    Confidence: ±0.008 (+0.002..+0.017) - [100.0%]

    2. Rollout¹ Bar/21 9/3 eq:-0.046 (-0.055)
    Player: 48.94% (G:18.48% B:1.80%)
    Opponent: 51.06% (G:19.37% B:1.13%)
    Confidence: ±0.008 (-0.055..-0.038) - [0.0%]

    ¹ 5184 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller

    eXtreme Gammon Version: 2.19.211.pre-release

    ---
    Tim Chow

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Stick Rice@21:1/5 to Tim Chow on Wed Nov 23 05:36:12 2022
    On Tuesday, November 22, 2022 at 9:06:39 AM UTC-5, Tim Chow wrote:
    XGID=-c-B--E-BAA-dBa----c--bbAA:0:0:1:64:0:0:0:0:10

    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O | | O O O X |
    | X | | O O O |
    | | | O |
    | | | |
    | | X | |
    | |BAR| |
    | | | X |
    | O | | X |
    | O | | X O |
    | O X | | X X O |
    | O X X X | | X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 146 O: 163 X-O: 0-0
    Cube: 1
    X to play 64
    I'm not sure about the answer to the question in the subject line,
    but regardless, none of the sixes is particularly pleasant to play.
    Being ahead in the race, I felt that the choice was between 24/18
    and 21/15. However, XG thinks both of those plays are whoppers
    with cheese. I think this position is a good illustration of
    Magriel's criteria, which all point toward a safe play; 9/3 may
    look ugly, but it's certainly safe.

    The variant below illustrates the same point about safety. With
    O's blot shifted to her 8pt, bar/15 becomes the safer play.

    1. Rollout¹ Bar/21 9/3 eq:+0.071
    Player: 51.19% (G:20.08% B:2.15%)
    Opponent: 48.81% (G:17.60% B:0.94%)
    Confidence: ±0.008 (+0.062..+0.079) - [100.0%]

    2. Rollout¹ Bar/21 10/4 eq:-0.009 (-0.079)
    Player: 50.27% (G:19.71% B:2.06%)
    Opponent: 49.73% (G:20.19% B:1.73%)
    Confidence: ±0.008 (-0.017..-0.001) - [0.0%]

    3. Rollout² Bar/21 24/18 eq:-0.064 (-0.134)
    Player: 49.47% (G:18.68% B:1.91%)
    Opponent: 50.53% (G:22.17% B:2.13%)
    Confidence: ±0.016 (-0.079..-0.048) - [0.0%]

    4. Rollout² Bar/15 eq:-0.096 (-0.166)
    Player: 48.77% (G:18.47% B:1.96%)
    Opponent: 51.23% (G:22.79% B:2.06%)
    Confidence: ±0.016 (-0.112..-0.080) - [0.0%]

    ¹ 5184 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller

    ² 1296 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller

    eXtreme Gammon Version: 2.19.211.pre-release

    -------
    Variant
    -------

    XGID=-c-B--E-BAA-dB---a-c--bbAA:0:0:1:64:0:0:0:0:10
    Score is X:0 O:0. Unlimited Game
    +13-14-15-16-17-18------19-20-21-22-23-24-+
    | X O | | O O O X |
    | X | | O O O |
    | | | O |
    | | | |
    | | X | |
    | |BAR| |
    | | | X |
    | O | | X |
    | O | | X O |
    | O X | | X X O |
    | O X X X | | X X O |
    +12-11-10--9--8--7-------6--5--4--3--2--1-+
    Pip count X: 146 O: 160 X-O: 0-0
    Cube: 1
    X to play 64
    1. Rollout¹ Bar/15 eq:+0.009
    Player: 51.19% (G:18.54% B:1.84%)
    Opponent: 48.81% (G:20.95% B:1.80%)
    Confidence: ±0.008 (+0.002..+0.017) - [100.0%]

    2. Rollout¹ Bar/21 9/3 eq:-0.046 (-0.055)
    Player: 48.94% (G:18.48% B:1.80%)
    Opponent: 51.06% (G:19.37% B:1.13%)
    Confidence: ±0.008 (-0.055..-0.038) - [0.0%]

    ¹ 5184 Games rolled with Variance Reduction.
    Dice Seed: 271828
    Moves: 3-ply, cube decisions: XG Roller

    eXtreme Gammon Version: 2.19.211.pre-release

    ---
    Tim Chow

    It is better to not have played a six.

    Stick

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Nasti Chestikov@21:1/5 to Stick Rice on Thu Nov 24 09:57:00 2022
    On Wednesday, 23 November 2022 at 13:36:13 UTC, Stick Rice wrote:

    It is better to not have played a six.

    Stick

    Amusingly, I thought the same but then thought I must have got it wrong.

    Glad that a top-notch player like Stick has backed up my instincts.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)